Camelina, scientifically known as Camelina sativa (L.) Crantz, is an ancient oilseed crop belonging to the Brassicaceae family, specifically to the tribe Camelineae. Also known as false flax or gold of pleasure, this crop has historical roots dating back to the Iron Age and was extensively cultivated in European countries and Russia, its center of origin. However, its cultivation declined after the Second World War due to the emergence of more profitable crops (Ghidoli et al., 2023a).

Characterized by average height ranging from 0.3 to 0.9 m, camelina plants feature branched stems and alternate lanceolate leaves. Its inflorescences form racemes comprising small yellow flowers with four petals, and its smooth, leathery siliques typically contain 5–15 golden/brown seeds, each measuring 2 to 3 mm in length. The weight of 1000 seeds ranges from 0.8 to 2.0 g (Government of Canada, 2012). Camelina stands out as a resilient plant with a rapid growth cycle of approximately 85–100 days for the spring varieties and 190–210 days for winter varieties, making it suitable for various low-input agronomic systems, especially in the context of climate change (Ahmad et al., 2022).

Camelina proves beneficial in intercropping and rotation systems, particularly in arid regions (Berti et al., 2016; Neupane et al., 2022). Winter genotypes stand out as optimal choices for winter cultivation, providing soil protection. Incorporating winter camelina as a cover crop serves to prevent erosion, fosters carbon sequestration in the soil, and additionally functions as a weed control measure by inhibiting their growth (Zubr, 2003; Sydor et al., 2022; Ghidoli et al., 2023b).

Regarding this, in recent years, great attention has been paid to brassicaceous species, including camelina, as cover crops with allelopathic activity (Ghidoli et al., 2023b; Pascual et al., 2024). Some studies report field experiments to study the effects of camelina used as a cover crop in rotation with maize, highlighting a reduction in root disease and greater growth and yields compared to maize crops which followed other cover crops such as rye (Acharya et al., 2020).These studies suggest potential benefits for using camelina as a cover crop before growing corn. The positive effects of cover crops on soil quality, especially in low-carbon or degraded soils and soil structure, prevention of erosion and mitigation of crop diseases nowadays are being widely studied (Acharya et al., 2020). Furthermore, there has been a surge of interest in this crop due to its versatile applications, serving as a new source of polyunsaturated fatty acids and proteins for feed, food, and bio-based products (Hajiazizi et al., 2024). Camelina oil is particularly attractive for its high oil content in seeds (up to 40%) and its substantial proportion of unsaturated fatty acids, including 30–40% alpha-linolenic acid, 15–25% linoleic acid, 15% oleic acid, and about 15% eicosenoic acid (Rodríguez-Rodríguez et al., 2021).

Despite its nutritional benefits, camelina oil and the protein cake derived from seed pressing contain antinutritional compounds such as glucosinolates, synapin, phytic acid, condensed tannins, and erucic acid (Russo and Reggiani, 2012). Among these, glucosinolates (GSL) pose a significant limitation, especially in feed applications (Murphy, 2016).

In this scenario, when selecting new varieties of camelina it is necessary to consider the main agronomic characteristics, including yield (expressed in seed size and competitive ability), earliness, and the reduction of antinutritional compounds such as glucosinolates. Breeding programs face challenges due to camelina’s allohexaploid nature (chromosome number 2n = 40, genome size 750 Mbp) and limited genetic variability (Ghidoli et al., 2023a; Blume et al., 2023). However, some goals were achieved, in fact Lolli and colleagues, through classical breeding using the pedigree method obtained an improved camelina line with lower glucosinolates content which allowed the incorporation of up to 20% camelina cake in the diet of laying hens without any adverse effects on animal welfare and health, eggshell quality, or production performance (Lolli et al., 2020). Recent findings in genomics studies are promising a great contribution to improve camelina by the use in the selection scheme of Marker-Assisted Breeding (Li et al., 2021).

In this work we present data on a breeding program involving crossing between two varieties selected on the basis of molecular data carried out from a characterization performed with molecular markers (SSRs) and subsequently by GBS (Genotyping by Sequencing) technique that helped us to choose the parental lines. The resulting new variety, named C1244, shows interesting traits coming from the two different genetic pools associated with spring and winter varieties used in this work.

Rotation and intercropping are both agricultural practices aimed at maximizing yield and sustainability while minimizing the negative impacts on the environment offering several benefits: maintain soil fertility and efficient use of resources, pest and disease management and weeds control contributing to Climate‐smart agricultural (CSA) (Tabe-Ojong et al., 2024). However, despite the undeniable usefulness of intercropping, this practice is currently underutilized in developed countries, while in developing countries, it remains fundamental for the food security in smallholders (Santalucia and Sibhatu, 2024). There are several reasons why intercropping is less commonly used in developed countries: specialization and monoculture, market demands, land ownership and policies, and a lack of specific breeding programs, particularly regarding cover crops (Rubiales et al., 2023). In recent years, camelina has been gaining considerable interest from the scientific community due to its ability to thrive in conditions with limited water resources and poor-quality soils, making it a sustainable alternative to traditional oilseed crops, due also to the short life cycle (85–100 days for spring varieties, 190–210 for winter varieties) (Ahmad et al., 2022; Pascual et al., 2024). Researchers are currently exploring camelina as a biofuel crop and a new source of protein and oil due to its high seed oil content of about 40%, rich in polyunsaturated fatty acids (including 30–40% α-linolenic acid, 15–25% linoleic acid, 15% oleic acid, and approximately 15% eicosenoic acid) (Rodríguez-Rodríguez et al., 2021; Arshad et al., 2022). Moreover, the residue from seed pressing, known as cake, can be utilized in animal diets as a source of proteins and oils (Hajiazizi et al., 2024). Despite its potential, the presence of glucosinolates (GLS), sulfur molecules involved in plant defense, limits camelina’s use in feed and food applications (Russo and Reggiani, 2012; Russo et al., 2014; Murphy, 2016). Nonetheless, camelina exhibits disease-suppressing properties, thanks to glucosinolates that exhibit fungicidal, nematocidal and bactericidal activities (Arora and Kaushik, 2003). In fact, several studies have also indicated that camelina as a cover crop mitigates root diseases and improves the growth and yields of various crops, highlighting its potential as a sustainable and integrated pest management strategy in agriculture, making it emerge as a promising cover crop with weed control potential (Acharya et al., 2020; Ghidoli et al., 2023b).

For example, in a study conducted in the USA, sowing winter camelina into standing maize and soybean crops prior to their harvest enhanced soil properties and increased overall system productivity (Berti et al., 2017). In another study conducted in semiarid Mediterranean areas, the potential of camelina to reduce the presence of corn poppy and its seed production was demonstrated as a valuable tool for Integrated Weed Management (IWM), using barley as the main crop (Codina-Pascual et al., 2022). Additionally, intercropping spring-sown field peas with camelina significantly suppressed weed coverage compared to monocropped pea plots (Saucke and Ackermann, 2006).

Despite the great potential of this crop, there have been few breeding efforts aimed at studying and improving some characteristics of this plant to enable its widespread use in rotation or intercropping with other crops (Ghidoli et al., 2023a). In particular, the genetic improvement of this crop, aimed also at intercropping purposes, should shorten the vegetative cycle, increase seed size (to facilitate mechanized sowing and harvesting), thus making spring utilization easier as well.

With the aim to develop a new camelina variety, we started a breeding program based on the study of a survey of two main cluster groups (spring and winter varieties) by using genetic tools. The first molecular analyses were conducted by using 16 SSRs reported from the work of Manca et al. (2014) on six winter varieties and five spring varieties (Manca et al., 2014). The results obtained allow us to discriminate the two different habits as reported in Figure 1 . This result was confirmed by using the genotyping by sequencing technique on two spring varieties (C1238 and C1243) and two winter varieties (C1237 and C1233) ( Figure 2 ) exploring the variability at a definitely higher genome-wide resolution. Moreover, the data collected through the GBS analysis might be further analyzed to identify variants affecting genes possibly correlated with seasonal differences. Our results confirmed the study conducted on various members of the camelina genus by Chaudhary et al. (2020), in which GBS was employed to analyze 193 camelina accessions belonging to different species. The results showed that camelina species were represented by two clusters, the spring-type varieties and the winter-type varieties, in particular, the winter-type camelina lines may probably, from a phylogenetic point of view, be derived from a hybridization between C. sativa and C. microcarpa (Chaudhary et al., 2020). This last hypothesis could explain the strong similarity of the F1 hybrid ( Figures 3B, C ) generated by our breeding program (started by crossing spring x winter varieties) and the results obtained by Tepfer et al. (2020) by crossing a C. sativa spring variety and C. microcarpa (Tepfer et al., 2020). We decided to cross a spring (C1243) with a winter (C1233) variety to maximize the genetic diversity selectable in our breeding program, based on bulk method selection for yield, earliness and weight of 1000 seeds. As reported before, the F1 hybrid showed in the first stage of development an intermediate characteristic of the two habits of varieties ( Figure 3B ) and a high hybrid vigor (shrubby habit, taller and more branched plants and woody stems with larger diameters) was shown on reaching maturity ( Figure 3C ). The results obtained suggest that a utilization of F1 seeds could be possible, in the near future, by using a male sterile mutation that so far, to our knowledge, has not yet been found. The new variety obtained (C1244) was cultivated in winter for two consecutive years with all the varieties under study reported in Table 1 .

The comparison of all the varieties allowed us to collect the data regarding the yield (kg/ha), the number of plants per m² and the weight (g) of 1000 seeds reported in Table 3 . In our work, we measured yields ranging from 3393 kg/ha to 1670 kg/ha ( Table 3 ), consistent with previously reported data for the Northern Italy region. In fact, Masella et al. (2014) reported a yield ranging from 1200 to 3300 kg/ha studying different varieties. Camelina, thrives in various soil types and grows particularly well in cool semi-arid climates. While it can endure drought, it may hinder delicate growth stages like flowering (Berti et al., 2016). However, the most abundant seed yields have been observed in Mediterranean climates where camelina cultivation is gaining more and more interest especially in Italy (Berti et al., 2016; Estakhr and Ranjbar, 2021).

Evaluating W1000, we found that on average the seed-size of spring varieties is higher compared to that of winter varieties (W1000 means respectively 1.31 and 1.15g) as shown in Table 3 . This result is in agreement with a previous work, where the winter and spring genotypes were differentiated by most seed shape descriptors and in particular by seed weight (Wiwart et al., 2019).

The new variety C1244 recorded a weight of 1000 seeds statistically higher than the two parents ( Figure 5C ), as well as the highest recorded in both agronomic years ( Table 3 ). The increase in seed weight obtained in the selection process is a positive parameter as for crops with small seeds this can lead to facilitating both sowing and harvesting operations.

A further trait of interest obtained from the output of our breeding program was the decreasing in the crop cycle ( Figure 5D ). C1244, thanks to the selection, flowers earlier than all the spring varieties under study. This trait holds significant importance in intercropping and rotation systems, especially in dry regions (Zubr, 1997; Berti et al., 2016; Neupane et al., 2022). Additionally, apart from its role in crop rotations, C. sativa can offer various ecosystem services, such as preventing soil erosion and nutrient runoff during early spring (Gesch, 2013) and providing habitat for pollinators (Eberle et. al., 2015). Although C. sativa yields relatively modest amounts of biomass compared to larger crops, its crop residues can enhance soil water absorption capacity, which is particularly beneficial in dry soil regions (Lohaus et al., 2020).

Taking together all the agronomic traits present in Table 3 and flowering data (data not shown) for all the varieties, PCA multivariate analysis clustered the two main camelina growing season habits, confirming again the genetic data ( Figure 6 ).

Bromatological analyses, concerning dry matter, crude fiber, ash, crude protein, and oil, and glucosinolate quantification were carried out on the collected seeds ( Table 4 ). The bromatological and glucosinolate analyses were conducted with the aim of assessing camelina’s suitability for use in both feed and food applications. A primary concern lies in the presence of glucosinolates (GLS), which represents a significant limitation for these applications. However, these molecules play a role in plant defense mechanisms, and, as noted by Ghidoli et al. (2023b), their occurrence can be attributed to the allelopathic properties inherent in camelina (Quéro et al., 2016; Hofmann et al., 2023). A positive correlation (r = 0.69; p = 0.013) was observed between protein and glucosinolate content ( Figure 8 ), and the same result was obtained in the previous study (Ghidoli et al., 2023c), in which two hypotheses were proposed to explain the correlation. The first hypothesis suggests that the presence of sulfur-containing amino acids, from which glucosinolates are synthesized, could account for this correlation, given the sulfuric nature of glucosinolates (Ghidoli et al., 2023b). The second hypothesis takes into consideration the 2008 study by Williams and colleagues, highlighting epithiospecifier proteins (ESPs) as non-catalytic cofactors of myrosinase—the enzyme responsible for catalyzing the hydrolysis of glucosinolates (Williams et al., 2008). According to this hypothesis, the correlation between protein and glucosinolate content may be attributed to the influence of ESPs on the glucosinolate levels (Lambrix et al., 2001; Wittstock and Burow, 2007; Williams et al., 2008; Kuchernig et al., 2012). Finally, also in this case, as shown in Figure 9 , PCA obtained using bromatological traits and glucosinolates content confirmed the presence of two distinct camelina agronomic behaviors.

Recognizing the significance of genetic diversity is crucial for formulating a resilient breeding strategy that involves identifying and integrating essential variations to enhance future crop improvement efforts. In this study, seed size emerges as a crucial factor influencing both a high oil yield and the improvement of all mechanized agricultural operations. The newly developed variety, C1244, demonstrated the most favorable combination of agronomic and chemical parameters. This suggests that classical breeding programs can prove beneficial in enhancing this species, even in the face of its limited genetic variability. Finally, the new variety, which is characterized by high yield, large seeds, and a short vegetative cycle, could be used both as a winter cover crop and in spring intercropping, particularly with legumes and cereals, to enhance the sustainability of these agricultural crops and improve European farming systems.

The raw data supporting the conclusions of this article will be made available by the authors, without undue reservation.

MG: Visualization, Writing – original draft, Software, Methodology, Investigation, Formal analysis, Data curation, Conceptualization. FG: Supervision, Writing – review & editing, Software, Methodology, Formal analysis, Data curation. SD: Writing – review & editing, Software, Methodology, Formal analysis, Data curation. SF: Writing – review & editing, Software, Methodology, Formal analysis, Data curation. ML: Investigation, Writing – review & editing, Supervision, Methodology. EC: Writing – review & editing, Supervision, Methodology, Formal analysis, Data curation. AS: Writing – review & editing, Supervision, Methodology. LR: Writing – review & editing, Supervision, Methodology. SP: Writing – review & editing, Visualization, Validation, Supervision, Resources, Project administration, Investigation, Funding acquisition, Conceptualization.